In the field of ambient illuminated, low-power, colored displays, an increasing number of technologies and systems have been proposed in recent years. The underlying technologies span from electrophoretic charged ink particles to nematic liquid crystal displays (LCD) to electro-wetting.
For example, an electrophoretic display uses charged ink (pigment) particles to form visible images. The charged ink particles are re-arranged using an applied electric field. Electrophoretic displays can be considered as electronic paper, because of their paper-like appearance and low power consumption.
Nematic displays include twisted nematic (TN) displays, super-twisted nematic (STN) displays and color super-twisted nematic (CSTN) displays. In a TN display, an electric field is applied to precisely control realignment of liquid crystal molecules between different ordered molecular configurations. This is achieved with little power consumption and at low operating voltages.
In electro-wetting, an electric field is applied to modify the wetting properties of a hydrophobic surface. Electro-wetting can be used in a wide range of applications from adjustable lenses to electronic displays (e-paper) and switches for optical fibers.